How do you explain the amphoteric behaviour of amino acids?
In aqueous solution, the carboxyl group of an amino acid can lose a proton and the amino group can accept a proton to give a dipolar ion known as zwitter ion.
Therefore, in zwitter ionic form, the amino acid can act both as an acid and as a base.
Thus, amino acids show amphoteric behaviour.
What happens when D-glucose is treated with the following reagents? (i)HI (ii)Bromine water (iii)HNO3
How do you explain the absence of aldehyde group in the pentaacetate of D-glucose?
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.
Define the following as related to proteins
(i) Peptide linkage (ii) Primary structure (iii) Denaturation.
What products would be formed when a nucleotide from DNA containing thymine is hydrolysed?
The two strands in DNA are not identical but are complementary. Explain.
Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
What are nucleic acids? Mention their two important functions.
Where does the water present in the egg go after boiling the egg?
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
Why are solids rigid?
Write any two characteristics of Chemisorption.
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
Why are pentahalides more covalent than trihalides?
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
Calculate the mass percentage of benzene (C6H6) and carbon tetrachloride (CCl4) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.
Calculate the efficiency of packing in case of a metal crystal for
(i) simple cubic
(ii) body-centred cubic
(iii) face-centred cubic (with the assumptions that atoms are touching each other).
Indicate the types of isomerism exhibited by the following complexes and draw the structures for these isomers:
(i) K[Cr(H2O)2(C2O4)2
(ii) [Co(en)3]Cl3
(iii) [Co(NH3)5(NO2)](NO3)2
(iv) [Pt(NH3)(H2O)Cl2]
Calculate the overall complex dissociation equilibrium constant for the Cu(NH3)42+ ion, given that β4 for this complex is 2.1 x 1013.
H2S, a toxic gas with rotten egg like smell, is used for the qualitative analysis. If the solubility of H2S in water at STP is 0.195 m, calculate Henry's law constant.
Give plausible explanation for each of the following:
(i) Cyclohexanone forms cyanohydrin in good yield but 2, 2, 6 trimethylcyclohexanone does not.
(ii) There are two -NH2 groups in semicarbazide. However, only one is involved in the formation of semicarbazones.
(iii) During the preparation of esters from a carboxylic acid and an alcohol in the presence of an acid catalyst, the water or the ester should be removed as soon as it is formed.
Describe the following:
(i) Acetylation
(ii) Cannizzaro reaction
(iii) Cross aldol condensation
(iv) Decarboxylation
What is the covalence of nitrogen in N2O5?
The half-life for radioactive decay of 14C is 5730 years. An archaeological artifact containing wood had only 80% of the 14C found in a living tree. Estimate the age of the sample.
What happens when PCl5 is heated?